Matlab:Refined population model
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% % REFINED MAGICAL GIRL-WITCH POPULATION MODEL % This file has been produced for FreeMat 4.0 % The syntax of the plot commands may differ from Matlab. % % If you want to modify the constants, please bear these restrictions in mind: % -C should be an integer % -D, B, N, K and P should be values in [0,1] % -B should be greater than K (or else, the number of witches will be negative) * -W(1) should be strictly positive. If W(1)=0, no witch appear ever, and MSes grow linearily % C = 100; % Number of girls contracted by QBe D = 0.25; % Proportion of girls (who are fighting) that die B = 0.125; % Proportion of girls (who are fighting) to become witches N = 0.015; % Proportion of familiars becoming witches K = 0.12; % Proportion of witches getting killed by MSes P = 0.8; % proportion of MSes fighting M(1) = 0; W(1) = 1; hold on for t=1:500 prop = P*min(M(t), W(t)); deltaM = C- prop*(D+B); deltaW = N*W(t) + prop*(B-K); M(t+1)=M(t)+deltaM; W(t+1)=W(t)+deltaW; end title('Evolution of the Magical Girls population over time') xlabel('time') ylabel('number of magical girls/witches') plot(M, 'g.-') plot(W, 'r.-') legend('Magical Girls', 'Witches', 'location', 'northeast') legend('boxoff') hold off